The total joint arthroplasty (TJA) market in the US is estimated to be over $9 billion by 2009. While TJA is a very successful procedure overall, this success is not the same for all joints. Researchers continue to look for opportunities to repair the damaged cartilage instead of replacing the joint. This is especially important in younger, more active patients who may outlive their first total joint implant and require a difficult and typically less successful revision procedure. Today, approximately 30% of US TJA patients are under 60 years old.
Joint distraction or Arthrodiatasis is a procedure that is currently being performed in Osteoarthritis (OA) patients for the ankle, hip, and knee joints with bulky external fixation devices. The current procedure involves inserting multiple pins or wires into the bones on each end of the damaged joint and connecting the pins or wires to an external fixation frame. The joint is then pulled apart (distracted) about 5 mm and held in that position for 2 to 3 months. Multiple peer-reviewed clinical papers report 70% or greater success rate with this procedure in the ankle (see clinical results table and article abstracts).
The arthritic ankle market is estimated to be over 50,000 procedures per year in the US and is growing at a 10% annual rate. Surgical treatment options for the arthritic ankle include ankle arthrodesis, total ankle replacement, and external ankle distraction. Each procedure has limitations and most orthopaedic surgeons agree there is not a good option for ankle arthritis. Some researchers believe this market is severely underserved and more than 375,000 patients suffer from arthritic ankles in the US alone.
Ankle Arthrodesis (Fusion) is the most common surgical treatment option for arthritic ankles with over 40,000 fusion procedures performed per year. Fusion limits the patient's motion and changes the gait pattern, which may lead to arthritis in the adjacent subtalar joint.
Total Ankle Replacement (TAR) is gaining popularity; however, this total joint replacement procedure does not have the same successful clinical outcome of hip and knee replacements. A recent meta-analysis reported 5-year implant survivorship at 78% compared to 96+% with total hip and knee replacements.
Joint Distraction with External Fixation (Arthrodiatasis) is a relatively new technique and is only performed by a small number of institutions. For example, the llizarov type ring fixator (mainly S&N and Small Bone Innovations) and the unilateral external fixator (Orthofix) each use external fixation systems for distraction. The procedures involve stretching the joint with an external fixation device and leaving the joint distracted for months while the cartilage heals. These techniques require a very large external frame and have patient drawbacks including discomfort and possible pin tract infections. Further, many total joint surgeons are not trained in the application of external fixation frames and find this procedure intimidating.
The present disclosure overcomes one or more shortcomings in the art.